Pin-tumbler lock



P. F. AUGENBRAUN. PIN TUMBLER LOCK. APPLICATION FILED SEPT. 15, 1921.

Patented J uly 11, 1922.

stars PETER F. AUGENBRAUN, 0F STAMFORD, CONNECTICUT, ASSIGNOB, TO THE YALE 8r, TOWNE MANUFACTURING COMFANY, OF STAMFORD, CONNECTICUT.

PIN-TUMBLER LOCK.

neeeeeo.

Application filed September To all whom it may concern: Be it known that 1, PETER F. AUGEN- vminim, a citizen of the United States, and

a resident of Stamford, in the county of Fair-field and State of Connecticut, have invented certain new and useful improvements in Pin-Tumbler Locks; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

"This invention relates to improvements in pin tumbler locks and more particularly to simple and efficient means whereby armor is provided in theplugof the loclr,.the object of the invention being to provide the plug of a pin tumbler lock with hardened steel members so located as to constitute armor which will prevent access to the tumblers by a boring tool.

With this object in view, the invention consists in certain novel features as hereinafter set forth and-pointed out in the claims.

In the accompanying drawings, Figure 1 is a sectional view partly in elevation show ing an embodiment of my improvements. Figure 2 is a front view. Figure 3 is a sectional view on the line 3-8 of Figure 2. Figure i is a detail View of one of the armor strips, and Figures 5, 6, 7 and S are views illustrating modified constructions.

1 represents the cylinder of a pin tumbler lock and the same may be provided at its front end with an armor 2 having dovetail connection therewith as at 3. The plug 4: of the lock is provided with a plurality of longitudinal slots 5 at respective sides of the key-way 6 and in these slots, hardened steel armor strips 7 are inserted. These strips may be madeof sheet steel and their inner edges made to form parts of the outline of the key-way and said inner edges are provided with recesses 9 (which may be punched out of Specification of Letters Patent.

Patented July M, 313 322.

Serial No. access.

the sheet metal) for the passage of the tumbler pins of the lock. In Figure 2 of the drawing 1 have shown the armor strips at respective sides of the key-way,--two at one side and one at the other but it is evident that only two such strips or a number greater than three may be employed, and said steel armor strip located in the plug as above e?- plained will effectually prevent access to the pin tumblers by a boring tool.

In the embodimentof my invention shown in Figures 5 to 8, the slots for the reception of armor strips are each formed by boring two holes 5 close together as clearly indicated in Figure 6 and each pair of such slots receive an armor strip 7 having a cross-section corresponding to the shape of the slot as shown in Figure 8. The armor strips 7 may be formed of drawn stock and their inner edges are notched or recessed as at 9 to allow the passage of the pin tumblers.

Having fully described my invention what I claim as new and desire to secure by Let tiers-Patent, is:

. 1. A plug for a pin tumbler lock provided therein adjacent to the key-way with a longitudinal slot, and a hardened armor strip in said slot, said armor strip having a notched inner edge to permit passage of the pin tumblers of the lock.

2. A plug for a pin tumbler lock provided therein with longitudinally disposed hardened armor strips located at respective sides of the key-way in said plug and having notches for the passage of the pin tumblers of the lock.

In testimony whereof, I have signed this specification in the presence of two subscribing witnesses.

PETER F. AUGENBRAUN. lVitnesses:

HERBERT A. BUTLER, CHAS. A. BERRY. 

